Inclusion Criteria:

          -  Diagnosis of myelodysplastic syndrome and one of the following:

               -  Cytopenias requiring red blood cell and/or platelet transfusions or neutropenia
                  (ANC <1 X109/L)

               -  IPSS score of INT-1 or higher at screening

               -  MDS with excess blasts in transformation as defined by FAB criteria (20-29% bone
                  marrow blasts) or

               -  Chronic myelomonocytic leukemia

          -  Age ≥18 years old

          -  Adequate renal and hepatic function defined as all of the following:

               -  total bilirubin ≤ 2.0 mg/dl, except in cases of Gilbert's disease;

               -  AST and ALT ≤2.5 institutional ULN;

               -  serum creatinine within normal institutional limits or estimated creatinine
                  clearance ≥60 mL/min/1.73 m2 by the Cockcroft-Gault equation

          -  ECOG performance status ≤2

          -  Ability to understand and willingness to sign an IRB approved written informed consent
             document (or that of legally authorized representative, if applicable).

          -  Females must be surgically or biologically sterile or postmenopausal or if of
             childbearing potential, must agree to use an adequate method of contraception during
             the study until 30 days after the last treatment. Males must be surgically or
             biologically sterile or agree to use an adequate method of contraception during the
             study until 30 days after the last treatment. Should a woman become pregnant or
             suspect she is pregnant while participating in this study, she must inform her
             treating physician immediately.

          -  Patients may have received up to 3 prior cycles of hypomethylator therapy (i.e.
             decitabine or azacitidine) prior to enrollment and may have received supportive care
             measures (growth factors, erythropoietin stimulating agents, transfusion, etc.

          -  Either enrolled in HRPO# 201011766 ("Tissue Acquisition for Analysis of Genetic
             Progression Factors in Hematologic Diseases"), which facilitates collection of blood,
             bone marrow, and skin for correlative studies, or consents to collection of blood,
             bone marrow, and skin as part of this protocol.

        Exclusion Criteria:

          -  Prior treatment with four or more cycles of hypomethylator therapy.

          -  Receiving concomitant chemotherapy, radiation therapy, or immunotherapy during the
             duration of treatment on protocol.

          -  Known seropositivity for or active viral infection with human immunodeficiency virus
             (HIV), hepatitis B virus (HBV), or hepatitis C virus (HCV). Patients who are
             seropositive because of hepatitis B virus vaccine are eligible. Patients who are
             seropositive for HCV, but have a negative viral load are also eligible. Documentation
             that the patients have completed a course of therapy for HCV is required and will be
             obtained.

          -  Uncontrolled intercurrent illness including, but not limited to, ongoing or active
             infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac
             arrhythmia, or psychiatric illness/social situations that would limit compliance with
             study requirements

          -  Pregnant and/or breastfeeding.